Automatic device, equipment and methods for handling objects

ABSTRACT

An automatic device for handling objects comprises gripping means attached to a guiding element contacting the object, an actuator connected to the external means transporting the device, and a switching mechanism that alternately changes the status of the pickup device between an object-engaging and respectively object-disengaging status each time the guiding element reaches the end-of-travel position to an object holder. A single external axial movement is performed for both transporting the pickup device and actuating the switch and the grippers. An original pickup device with radially gliding pierced grippers crossed by curved arms attached to the axially moving actuator is disclosed, as well as a simplified object-handling robot and methods for using them, with emphasis to CD/DVD handling applications.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional patentapplication serial No. 60/556,857 filed Mar. 27, 2004 References Cited,U.S. Patent Documents 4253695 March, 1981 Blaive et al. 294/95;294/86.25; 294/110.1 4411576 October, 1983 Smith et al. 414/225. 4676710June, 1987 Shiraishi 414/225. 5165340 November, 1992 Karlyn et al.101/126. 5275424 January, 1994 Watanabe 279/2. 5503446 April, 1996 DeJong 294/94. 5698030 December, 1997 Rubenchik 118/500. 5797639 August,1998 Zorzenon 294/110.1; 294.112 5873692 February, 1999 Costas. 5897153April, 1999 Philipps 294/93; 294/95 5946216 August, 1999 Hollerich364/478. 5997204 December, 1999 Ducrocq 6111847 August, 2000 Assadian369/36. 6141298 October, 2000 Miller 369/30. 6220640 April, 2001 Jensen294/93; 294/100 6257636 July, 2001 Hovis. 294.110.1; 294/82.32; 294/1166321649 November, 2001 Vangen 101/35; 101/4; 206/307; 206/308.1 6532198March, 2003 Miller 6547296 April, 2003 Perkitny 294/16; 294/28;294/110.1 et al.

BACKGROUND OF THE INVENTION

The invention relates to automated devices and equipment for handlingobjects, with emphasis to devices and equipment used for handlinginformation-storage medium objects such as compact discs.

Many technologies require objects to be automatically and repetitivelytransported to/from specified locations in order to be processed. A widediversity of pick-up devices and specialized equipment for transportingand processing such objects has been developed during the last twodecades within the media industry, for processing of recordableinformation carriers like CD and DVD. Some of the most relevant onesrelated with the invention disclosed here are referenced in the patentlist included.

Various solutions are used for engaging/disengaging the objects to betransported: vacuum driven suction devices (U.S. Pat. No. 6,141,298),protruding grippers attempting to grasp the object from beneath (U.S.Pat. Nos. 5,275,424, 5,503,446, 5,897,153, 5,946,216, 6,220,640) or, forbored objects, friction grippers pushed against the inner wall of thehole of the object (U.S. Pat. Nos. 5,873,692, 6,111,847). Most knownsolutions require means for transporting the pick-up device against theobject holder and, respectively, separate means for actuating the pickerin order to engage or disengage the object. Regularly the transport armhas to carry not only the pickup device but its electromechanicalactuators and associated sensors, too, along a large rigid frame orshaft, exceeding the height of the object stacks (U.S. Pat. Nos.5,698,030, 5,873,692, 5,914,918, 5,946,216, 6,111,847, 6,141,298,6,321,649, 6,532,198). The higher the object stacks are, the bigger andmore expensive the automated handling equipment. Due to the lack offlexibility in transporting and positioning the picker against theobject holder, associated with the rigid catch of the object, most knownsolutions encounter picking errors, like dropping the object duringtransport or simultaneously engaging two objects.

Automated grippers eliminate the need for a vertical travelingtransporting arm and actuators (U.S. Pat. Nos. 5,797,639, 6,257,636,4,253,695). However, existing solutions are either too complex orinappropriate for applications where high precision is needed in orderto separate thin stacked objects, such as CD/DVD. A simpler automaticpickup device is needed, preferably able to grip the object from beneathin order to secure it during transport.

Currently many CD/DVD processing equipment does not allow a horizontaldisk to be vertically placed directly into the tray of their processingunits, a part of the circular disk holder being masked by the frontcover of the equipment (FIG. 6A). There haven't been any methodspreviously known for automatic loading/unloading disks into suchequipment.

BRIEF SUMMARY OF THE INVENTION

The present invention discloses a pickup device for gripping, holdingand releasing similar objects, such as compact discs, able toalternately switch between object engaging/disengaging statuses byitself, using a previously known self contained switching mechanism,automatically triggered each time the device reaches an end-of-travelposition to an object holder. There is a single external axial movementperformed for both transporting the pickup device towards the objectholder and engaging/disengaging the object, thus simplifying theautomation equipment and decreasing its cost.

The pickup device comprises a guiding element with a stopping shoulderenabling self adjustment to an optimal position when placed against theobject. Unlike some other known automatic grippers (i.e. U.S. Pat. No.6,257,636), the grippers are secured to the said guiding element incontact with the object and, when engaging the object, the grippers areactuated before the said guiding element starts moving. This featureenables gripping precision, important especially when working withstacked objects that have to be separated.

A new solution for gripping the object is disclosed: pierced grippingblades housed inside the guiding element are penetrated by thin curvedarms rigidly attached to an actuator, connected to the externaltransport means, axially moving with respect to the guiding elementwithin a short travel range. The arms are axially moving together withthe actuator and glide through the holes of the gripping blades, forcingthe protrusive grippers to radially glide out their housing engaging theobject or respectively retract inside the guiding element releasing theobject, accordingly with the pickup device status. These features allowerror free operation of the pickup device and a single external actionperformed for both axial transport of the pickup device and actuatingthe grippers. When appropriate, the grippers may glide under the object,supporting it from beneath. This way the object is secured duringtransport and the arms are relieved from tension, the burden beingsupported by the gripping blades.

Unlike previously known automatic grippers, the pickup device disclosedherein is meant to use a regular switching mechanism like the ones usedby retractable ball-point pens, rather than a customized, dedicated one.A simple two components mechanism is being used, like, for example, theone described in U.S. Pat. No. 5,997,204. Consequently the entireconstruction is simplified. One component of the switching mechanism isrigidly attached to the actuator so they axially move together whendriven by the transport means. The second component of the switchingmechanism is attached to the guiding element by a retaining pin andallowed to spin around the common axis, but not to move away axially.

For applications where the objects are to be lifted, the hanging pickercan be vertically ascended and descended using flexible means, likethread, wire, flexible ribbon or tape. This way there is no need neitherfor a vertical traveling supporting arm, nor for a frame or a verticalshaft for the picker to travel along. The object handling robot becomesvery simple and small, allowing though long vertical travel for thepicker, said large automated processing capacity.

A wide variety of CD/DVD processing equipments could be automated bysuch a versatile robot placed above the said master equipment, where thedisks are vertically stacked and delivered to/from retainers locatedunder the surface supporting the robot and accessed from above. Onepossible embodiment is shown in FIG. 7. Depending on the amount of disksto be processed, the user can choose the number and the positions of thedisk retainers to be used during each automated processing cycle. Theinvention discloses a simple, fast and effective procedure forpositioning the disk retainers, where the robot delivers to the selectedlocation a positioning device and the user transfer the retainer overthe positioning device and takes the device away (FIG. 9A-C).

Currently many CD/DVD processing equipment does not allow a horizontaldisk to be vertically placed directly into the trays of their processingunits, a part of the circular disk holder area being masked by the frontcover of the equipment (FIG. 6A). A method and a correspondingembodiment are disclosed where the disk is inclined toward theprocessing equipment when lifted from its horizontal tray by thevertically moving pickup device, and glides into the tray from itsinclined position to a final horizontal position when verticallydelivered by the picking device into the tray, allowing automaticloading/unloading disks into such processing equipment (FIG. 5, FIG.6A,B).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A-C are perspective views of prior art switching mechanism indifferent statuses

FIG. 2 is a cross-section view of the pickup device placed against thestacked objects

FIG. 3 is a cross-section view of the pickup device in object-disengagedstatus

FIG. 4A-B are cross-section views of the guiding element along thegripper's housing plane, two embodiments

FIG. 5 is a cross-section view of the pickup device in object-engagedstatus, disk inclined embodiment

FIG. 6A-B are schematically views of a processing unit with a trayhaving partially masked disk holding area and of the trajectory of aninclined disk being vertically transported to/from such a tray

FIG. 7 is a perspective view of one possible embodiment of a robot

FIG. 8 is a cross-section view of the pickup device in object-engagedstatus, horizontal disk embodiment

FIG. 9A-C show the sequences for positioning a stack retainer: the robotdelivers the positioning device to the selected location, the usertransfer the retainer over the positioning device and takes the deviceaway.

DESCRIPTION

Many technologies require objects to be automatically and repetitivelytransported to/from specified locations in order to be processed. Thepickup device has to alternately pick-up the object from one sourcelocation and respectively to release it at the destination location. Thepresent invention discloses a pickup device for gripping, holding andreleasing similar objects, such as compact discs, that does not requireany additional external actuation for gripping the object, being able toalternately switch between object engaging/disengaging statuses byitself, by means of a self contained switching mechanism, automaticallytriggered each time the device reaches an end-of-travel position to anobject holder. For ease of the description the various handled objectswill be referred herein as “disks”. For simplicity, in the preferredembodiment described, the object holders are horizontal, the disks arevertically stacked and the pickup device moves vertically along the axisof the object holder in order to engage or disengage a disk, beingsubsequently transported above a different location.

Many types of previously known switching mechanisms can be used, likethe ones used by retractable ball-point pens or some push-buttonelectric switches. For simplicity, the pickup device disclosed hereinuses a mechanism like the one described in U.S. Pat. No. 5,997,204. Itsfunctioning is only briefly described here, in order to ease furtherdescription of the pickup device itself. The switching mechanism (FIG.1A-C) comprises two parts: a cylindrical pin 2 having two pairs ofdiametrically opposed protruding ribs 3 and a cylindrical ring 1comprising grooves and saw-teething on its inner surface (not shown).Considering the mechanism positioned vertically and pin 2 allowed torotate, when the ring 1 is axially moved upwards along the central pin2, the ribs glide on the inclined surface of the teeth, the pin rotatesand the ring stops like shown in FIG. 1A, when the upper ribs 3 reachthe deepest points of the current saw-teeth grooves, so the ring gripsthe pin. This position will determine a “disk engaged status” within thefurther description of the pickup device. Afterwards, when the ring 1 isaxially moved downwards to the opposite direction, the other pair ofribs glides on the saw-teething on the other side of the ring, the pinrotates and the ring stops as shown in FIG. 1B, when the ribs reach thedeepest points of the current saw-teeth. We will refer it as a“switching position”. When subsequently the ring is moved upwards again,the process repeats, but the ring will grip the pin and stop after ashorter vertical travel, as shown in FIG. 1C, due to the different shapeof the corresponding saw-teeth. This position will determine a “diskdisengaged status” within the further description of the pickup device.Each reaching of a “switching position”, will determine subsequentchange of status for the picking device: always a “disk engaged status”will be followed by a “disk disengaged status” and vice versa.

A guiding element 6 having a stopping shoulder 7 enable the pickingdevice to self adjust its position to an optimum when placed against theobject, like shown in FIG. 2. A central pin 5 connects the guidingelement with the pin 2, component of the switching mechanism, allowingpin 2 to spin around the common central axis.

The actuator 4 attached to the external axial movement means 12, bywhich the entire pickup device is transported, comprises a centralcylindrical bore that houses the ring 1, component of the switchingmechanism. The ring 1 is rigidly attached to the actuator 4.

Each time the guiding element 6 stops on an object holder, the actuator4 continues its axial movement until eventually gets closest to theguiding element, when the mechanism reaches its switching position. Whenthe transport means 12 pulls 4 away from 6, the distance the twoelements can get apart, before element 6 starts moving along with 4,depends on the current status of the switching mechanism and alternatesbetween a short and a long travel. This feature allows the pickingdevice to alternate between object-engaging and object-disengagingstatuses, the gripping means being actuated by the element 4 moving withrespect to 6. Unlike some other known automatic grippers (i.e. U.S. Pat.No. 6,257,636), the grippers are secured to the said guiding element incontact with the object and, when engaging the object, the grippers areactuated before the said guiding element starts moving. This featureenables gripping precision, important especially when working withstacked objects that have to be separated.

For the preferred embodiments described herein, the axial distancebetween the stopping shoulder 7 and the sharp edges of the grippingblades 9 housed inside the recess 16 is slightly bigger than thethickness of the disk 15, allowing the protruding blades 9 to grasp thedisk from beneath when actuated.

The gripping blades 9 comprise holes 10 for the thin curved arms 8,rigidly attached to the element 4, to cross through. The guiding element6 has thin radial ditches 11 allowing the arms 8 to travel freely whenthe element 4 is axially moving against the guiding element. An optionaldust-protective frame 14 may be rigidly attached to the guiding element6, provided that it allows room for the element 4 to move axially withrespect to the guiding element within its entire travel range. Theoptional frame 14 should comprise a hole 13 on its top, opposite to theguiding element, for the transport means 12 to cross through.

When the element 4 is axially pulled away from the guiding element by12, the arms 8 glide along the ditches 11 and through the holes 10 ofthe pierced blades 9 and, if the switching mechanism allows element 4 torise enough, namely the pickup mechanism is in “disk engaged status”,they push the grippers 9 to glide out their housing 16, then the guidingelement 6 starts moving together with element 4, that is the entirepickup device 21 is being moved by 12.

Suppose the picking device placed against a stack of disks as shown inFIG. 2, with the shoulder 7 laying on the top disk. The element 4 isclosest to the guiding element 6 and the arms 8 keep the gripping blades9 completely retracted inside their recess 16. The mechanism is in“switching position”, like in FIG. 1B. Furthermore, suppose the pickingdevice was in “disk disengaging status” when placed against the stack,so we expect it to engage the disk next time when lifted from the stack.When the transport means 12 axially pulls element 4 away from theguiding element 6 resting on the disk beneath, the arms 8 glide throughthe holes 10 of the pierced blades 9 and push them to glide out of theguiding element, their sharp edges protruding under the first disk instack. Then the guiding element 6 starts moving together with theelement 4, namely the entire pickup device 21 is lifted by 12, carryingaway the disk 15 so engaged, as shown in FIG. 5. The section views inFIG. 4A and FIG. 4B show the radial movement of the blades in twopossible embodiments, with a single gripping blade and respectively withmore gripping blades. FIG. 8 shows such a multiple gripping bladesembodiment of the pickup device in “disk engaged status”, where the diskkeeps its horizontal position during transport.

Suppose now the disk so engaged is transported to be released to a newlocation. The transport means 12 vertically lowers the pickup device onlocation and, when the disk reaches the holder, the guiding element 6,with its shoulder 7 laying on the disk, stops. The actuator 4 continuesits movement, approaching the guiding element. The arms 8 glide throughthe holes 10 of the pierced blades 9 forcing them to retract completelyinside the guiding element 6. The movement stops when the element 4reaches its lowest position, closest to the guiding element, when thepickup device is in “switching position”, as shown in FIG. 2.

Next lift will find the pickup device in “disk disengaged status”, sothe mechanism will determine the element 4 to grip the guiding element 6after a short travel, before the arms 8 start pushing the grippers 9out, so the gripping blades will not protrude out of the guidingelement, therefore the pickup device 21, lifted by 12, will leaveunloaded as shown in FIG. 3 and the disk will remain in its holder.

The cycle is permanently repeated, the pickup device alternating betweendisk engaging/disk disengaging statuses each time it reaches thedown-end-of-travel position to an object holder.

In the particular embodiment described, where the pickup device movesvertically towards the disk holder in order to engage or disengage adisk, the device can hang gravitationally, being ascended/descendedusing flexible means 12 like thread, wire, flexible ribbon or tape. Sucha solution dramatically simplifies the automation equipment, since thereis no need neither for a vertical traveling arm, nor for a frame or avertical shaft for the picker to travel along. Moreover, long verticaltravel for the pickup device, namely large capacity for the diskhandling robot can be achieved, even though the robot itself is smalland basically flat, the transporting flexible wire 12 being simplycoiled on a reel inside the robot and guided out on a pulley attached tothe horizontally moving part of the robot. The pickup device 21 islifted up to its highest position where a basically cylindrical holderunder the pulley houses it, keeping its vertical position and preventingit from waggling during the horizontal movement from a disk holder toanother. The robot should be positioned in such a way that it can accessfrom above the disk holders, namely the trays of the disk processingequipment and the stacks for processed/unprocessed disks.

A possible embodiment is shown in FIG. 7, where the robot 22 is placedover a disk processing master equipment 20, comprising processing units25, provided with trays 18. Requests for disk changing arecorrespondingly sent to the robot by the master equipment wheneverneeded, for example via RS232 interface. Disk retainers 24 for the diskstacks are placed on the table, around the master equipment served bythe robot. The robot may comprise a keyboard 23 for interfacing with thehuman operator. Depending on the number of disks to be processed, theuser can choose the number and the positions of the disk retainers 24 tobe used during each automated processing cycle. Once the configurationselected, the user have to place the disk retainers on the table,precisely at the locations further accessed by the robot. The followingprocedure will be reiterated for each disk retainer to be positioned:

-   -   the user selects the desired location with the keyboard 23 and        places on the tray 18 a positioning device 27, basically        cylindrical shaped and hollowed, comprising a top cover with a        central hole similar with a regular disk, so the robot can        handle it like an ordinary disk    -   the robot picks up, transports and releases the positioning        device 27 on the table to the selected location, then the pickup        device 21 ascends into its housing (FIG. 9A)    -   the user transfers over the positioning device 27 so located a        supporting device 26, basically ring shaped, comprising an        opening that fit the outer size of the positioning device so it        surrounds the positioning device and attaches to the table, for        example by self sticking means (FIG. 9B)    -   the user takes away the positioning device (FIG. 9C) and places        over the supporting device so fixed on the table the disk        retainer whose bottom shape mates the shape of the supportive        device in such a way that the retainer cannot move horizontally.        For CDs or DVDs, the original plastic cylindrical covers of        regular commercial disk spindles packages can be used as disk        retainers.

Currently many CD/DVD processing equipment does not allow a horizontaldisk to be vertically placed directly into the trays 18 of theirprocessing units, a part of the circular disk holder area being maskedby the front cover 19 of the equipment (FIG. 6A). If the disk isinclined towards the processing equipment during vertical travel alongthe central axis of the circular disk holder of such a tray, it may betransported to/from and delivered into the tray without interfering withthe said front cover masking 19, as shown in FIG. 6B. The embodiment ofthe pickup device shown in FIG. 5 can deliver a disk to/from such a trayas follows: the gripping blade hooks the disk asymmetrically, from thepart opposite to the equipment. When lifted, the disk inclines towardsthe processing equipment up to the desired angle, about 45 degrees, whenit reaches the stopping shoulder 17 on the guiding element. The shape ofthe guiding element itself is important since it has to allow the diskto rotate freely, preventing it from falling, too. The transport means12 must not allow the pickup device to spin around its axis, so the diskmaintains its inclined position towards the equipment during itsvertical travel. When the disk is vertically descended in order to bereleased into the tray, its lower edge glides into the tray and the diskrotates from its inclined position to the final horizontal position, asshown in FIG. 6B.

1. A pickup device for gripping, holding and releasing similar objects,where the device is transported to/from object holders on a directionalong its central axis and comprise: a guiding element allowing optimalalignment of the device with the said object, having a stopping shoulderlaying on the object when the said device is placed against the objectgripping blades housed inside the said guiding element, being able toglide in radial direction, each such a blade comprising a hole for acorresponding driving arm to cross through an actuating element,connected to the external means by which the pickup device istransported, that can be axially moved with respect to the mentionedguiding element within a short travel range, comprising thin curved armsrespectively included in radial planes, the said arms being axiallytranslated together with the said actuator, the said arms crossing thesaid pierced gripping blades forcing them to glide in/out the guidingelement in radial direction, simultaneously with the axial movement ofthe actuator against the guiding element, towards the object in order togrip it and respectively in opposite direction in order to release theobject
 2. Apparatus as claimed in claim 1, characterized in that thesaid blades have sharp gripping edges and the axial distance between thesaid stopping shoulder and the said edges when the blades extend out ofthe guiding element is slightly bigger than the thickness of the handledobject, the protruding blades gripping the object from beneath
 3. Apickup device for gripping, holding and releasing CD/DVD type disks,vertically transporting the said disk to/from a horizontal tray of aprocessing unit, characterized in that: the pickup device determines thesaid disk to incline towards the processing unit when vertically liftedfrom the horizontal tray the pickup device compels the said disk tomaintain its inclined position towards the processing unit during thevertical travel to/from such a horizontal tray of the said unit thepickup device allows the said disk to glide into the tray from itsinclined position to a final horizontal position when verticallydelivered into the mentioned horizontal tray
 4. An automatic pickupdevice for gripping, holding and releasing objects, where the device istransported to/from object holders on a direction along its central axisand comprises: a guiding element with a stopping shoulder allowingoptimal positioning of the device to the said object when the saiddevice is placed against the object an actuator, connected to theexternal means by which the pickup device is transported, that can beaxially moved with respect to the mentioned guiding element within ashort travel range a two components switching mechanism that alternatelychanges the status of the said pickup device between an object-engagingand respectively object-disengaging status each time the said pickupdevice reaches the end-of-travel position to an object holder, theswitching mechanism being triggered by the axial movement of theactuator against the guiding element stopped at the object holder, oneof its components being rigidly attached to the said actuator and theother one being connected to the guiding element gripping means securedto the said guiding element, actuated by the axial movement of the saidactuator with respect to the said guiding element, gripping the objectwhen the pickup device is in the object-engaging status and respectivelynot gripping it when the pickup device is in the object-disengagingstatus, when the said device is moved away from the object holder
 5. Anobject transporting robot using a device as claimed in claim 4, whereinthe said device is vertically moved using flexible means on which thepickup device hangs gravitationally
 6. A robot for handlinginformation-storage medium objects, serving an object processing masterequipment, gripping/releasing, vertically lifting/lowering andhorizontally transporting such objects from/to vertical stack retainersto/from one or more processing units of the said equipment, wherein therobot is placed above the master equipment and the stack retainers areplaced under the horizontal plane supporting the robot
 7. An interactivemethod for positioning the stack retainers accessed by a robot asclaimed in claim 6, where the said retainers are placed by the user toselected locations, on the same table with the processing equipment,reiterating for each stack to be used a positioning procedure comprisingthe following steps: the user places to a determined location accessedby the robot a positioning device and selects the location of the diskretainer to be positioned the robot picks up the positioning device,transports and releases it to the said selected location the usertransfers a stack-retaining support over the positioning device soplaced by the robot at the selected location